In tunneling and in mines there is often a need for suspending different devices used in the work, for example ventilators, drilling equipment and the like. Additionally, in mines and in tunneling one often uses platforms in order to transport excavated material and other material. These platforms are hung up in the roof of the tunnel or mine, which for example may be done by attaching a beam in the roof and then fastening the platform to the beam.
In order to fasten such devices, for example a service platform, to the roof, bolts of different types may be used. Often one uses expandable bolts, so called swelling bolts where the bolt comprises a tube, the interior of which is pressurized by means of a pressure means, such as a high pressure fluid, and thereby expands. An example of such an expandable bolt is showed in the Swedish patent nr. 7902129-1. The expansion bolts may be used with a special coupling, that is fastened to the expansion bolt. The platform, or the devices that one wishes to suspend in the roof, is then fastened in these couplings.
A disadvantage with using these bolts as suspension devices is that they, together with the special suspension coupling, protrude substantially from the roof of the tunnel, and must therefore be cut and/or covered by a thick layer of rendering concrete. This is a costly and time-consuming operation and it would be desirable to be able to minimize it. This bolt with suspension device may not be ranked as supporting of rock in the safety estimates.